Delanceyplace.com 5/12/09 - The Computer Mouse

In today's excerpt - the computer mouse. In 1964, Douglas Engelbart of the Stanford Research Institute (SRI) invented what became known as the computer mouse. It was called the mouse because it was "chased" by the cursor on the screen, then known as a CAT:

"Engelbart had almost - but not quite - hit upon the concept of the mouse in his original 1962 paper. With his NASA funding, he began exploring pointing devices and became interested in the problem of selecting text or graphics objects that were displayed on his screen. The goal of the study was to discover which device would allow a user to get to a given point on the screen most quickly as well as repeatedly with the fewest errors. ...

"Other kinds of pointing devices were already in use, including light pens, trackballs, and tablets with styli. The RAND Corporation had invented the latter, and though Engelbart hoped for a while that he could persuade them to lend him one for their research, the company told him it didn't have any available.

"The actual idea of a rolling, handheld pointing device came to Engelbart one day when he was at a computer-graphics conference. As he often did, he was feeling like an outsider, because everyone was talking, and he was uncomfortable and having trouble making himself heard. At times like this, he frequently tuned out and dropped into his own reverie. ...

"Pulling a small notepad from his shirt pocket, he made a quick sketch of a device that would track movement across a desktop. The idea was to use the two wheels to drive two potentiometers - devices that would register varying voltages as they were turned. Each one would move depending on the degree to which the wheels turned, and the resulting voltage could then be translated into the position of a cursor - they originally called it a 'bug' - on the screen. ...

"[He] turned to an SRI draftsman to carve an elegant, hand-sized lacquered pine case large enough to contain the two wheels and two potentiometers, and then gave the case to a craftsman at the SRI machine shop to manufacture the other mechanical components. The original mouse that the team assembled was large and bulky, in part because of the size of the available potentiometers. [Bill] English had also figured that he would need a device that would roll about five inches, a distance that could be translated into the width of the screen. That, in turn, required large wheels, which would rotate only once in five inches of travel.

"Although it is commonly believed that the story of how the mouse got its name has been lost in history, Roger Bates, who was a young hardware designer working for Bill English, has a clear recollection of how the name was chosen. ... He remembers that what today is called the cursor on the screen was at the time called a 'CAT.' Bates has forgotten what CAT stood for, and no one else seems to remember either, but in hindsight it seems obvious that the CAT would chase the tailed mouse on the desktop."

John Markoff, What the Dormouse Said: How the 60's Counterculture Shaped the Personal Computer, Penguin, Copyright 2005 by John Markoff, pp. 54-56.